1. Field of the Invention
The present invention relates generally to elevator systems. More particularly, the invention concerns novel connector brackets and the method of using the same for installing elevator car and counterweight guide rails within an elevator shaft.
2. Discussion of the Prior Art
A typical prior art electric power elevator system has an elevator shaft or hoistway within which guide rails are mounted to guide the vertical travel of elevator cars and counterweights. As a general rule, two elevator car guide rails and two counterweight guide rails are affixed to the building structure at spaced-apart locations.
In a typical prior art construction, a plurality of first support right angle brackets are connected at vertically spaced locations to the walls of the building structure that form the elevator shaft. By way of example, when poured concrete walls define the hoistway of the building structure, anchor bolts or like connectors are used to securely affix the first legs of each of the first brackets to the concrete walls. When steel beams define the hoistway of the building structure, the first leg of each of the brackets is generally welded to the steel beams at selected, spaced-apart locations. To position the car rails and counterweight rails within the hoistway, the outwardly protruding second legs of the first and second brackets are first clamped together in proper alignment and then are permanently connected together by welding. When the distance between the walls that define the hoistway and the guide rails is substantial, spanner plates are typically used to span and connect together the second legs of the first and second right angle brackets. When the car guide rails and the counterweight guide rails are correctly positioned within the hoistway of the building, conventional roller assemblies mounted on the cars and on the counterweight assemblies travel along the guide rails to guide the vertical travel of the cars and counterweight assemblies within the hoistway.
Similar constructions are employed in typical prior art hydraulic power elevator systems. However, in such systems, counterweights are not used and, therefore, only elevator car guide rails need to be installed within the building hoistway. The elevator car guide rails of the hydraulic systems are usually quite similar to those used in electric power systems and are typically installed in a similar manner.
In accordance with typical prior art installation procedures, a plumb line is first established within the hoistway along a vertical line that is intended to locate the faces of the second guide rail right angle brackets to which the guide rail is to be connected. Because of the vagaries of building construction, the brackets typically do not initially align with the plumb line and often considerable adjustment is required prior to finally permanently interconnecting the guide rail brackets with the support brackets that are affixed to the walls of to hoistway. As a general rule, in initially positioning the guide rails within the hoistway, the guide rail or second angle brackets must be moved within a generally horizontal plane toward and away from and also from side to side relative to the support brackets. After the rail brackets are appropriately positioned relative to the support brackets they are temporarily connected to the support brackets by suitable clamps. With the brackets thusly clamped together, they are permanently connected by welding the horizontally extending legs of the rail brackets to the horizontally extending legs of the support brackets. This done, the elevator car roller assemblies and the counterweight roller assemblies are operably interconnected with their respective guide rails.
The prior art installation methods described in the preceding paragraph are cumbersome and time consuming even in new construction. However, in retrofit constructions, the procedures are particularly difficult. For example, when the elevator systems in hospitals, schools, and other public buildings are retrofitted, the welding step is quite hazardous and most undesirable. This is because, during the retrofit operations, welding of the rail brackets to the support brackets results in noxious welding gases and fumes unavoidably spreading throughout the building. Particularly in hospitals and schools, these noxious welding gases can be both unpleasant and hazardous and can, on occasion, result in serious complications to the persons exposed to the noxious fumes.
It is this major drawback of the prior art processes that the present invention seeks to avoid by providing uniquely configured, readily adjustable support and guide rail brackets that can be safely and securely interconnected together by special bolts rather than by welding. As will be better understood from the description which follows, the connector legs of the support and guide rail brackets of the present invention are provided with a plurality of strategically arranged, indexable connector holes that permit the necessary degree of adjustment of the brackets to properly position the guide rails within the hoistway. When selected pairs of connector holes provided in the brackets are appropriately aligned, the brackets can be securely bolted together using specially configured bolts that provide substantial structural integrity and positively preclude shifting of the brackets even as a result of projected seismic loading.